Woodturner's Resource
Woodturner's Resource  
  Featured Artist    Websites   Support Wr
Tutorials, Projects & Tips   Event Calendar   Tool and Book Store
  Home Page Forum HelpSearch Map TPT Resources LoginRegister
 
Page Index Toggle Pages: 1
Send Topic Print
Scraper Burnishing tool (Read 1,642 times)
 
JimQuarles
WR Addict
WR Patron
*****
Offline


WR Rocks, BIG Time!

Posts: 13,194

Glendale, AZ, Arizona, USA
Glendale, AZ
Arizona
USA

Gender: male
Scraper Burnishing tool
Sep 4th, 2005 at 6:16pm
 
Seems to me that I remember seeing a jig for burnishing scrapers.  It had a black base and hardened steel rods that stuck at the correct angle.  Anybody know what I am talking about?  Who makes it, or sells it?

Thanks JimQ
Back to top
  

Mentor Basics, Pens, small stuff, Acrylics, EasyRougher.
Just Turnin' Around! Glendale, AZ Cool Cool

"Right now I'm having amnesia and deja vu at the same time.
I think I've forgotten this before." - Steven Wright
 
IP Logged
 
Gil Jones
Ex Member


Re: Scraper Burnishing tool
Reply #1 - Sep 4th, 2005 at 6:40pm
 
Check this out Jim.
Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to Login or Register
Back to top
  
 
IP Logged
 
JimQuarles
WR Addict
WR Patron
*****
Offline


WR Rocks, BIG Time!

Posts: 13,194

Glendale, AZ, Arizona, USA
Glendale, AZ
Arizona
USA

Gender: male
Re: Scraper Burnishing tool
Reply #2 - Sep 4th, 2005 at 7:17pm
 
Gil,
Thanks.  I knew I had seen something a while ago, but could not find it anywhere now. 

JimQ
Back to top
  

Mentor Basics, Pens, small stuff, Acrylics, EasyRougher.
Just Turnin' Around! Glendale, AZ Cool Cool

"Right now I'm having amnesia and deja vu at the same time.
I think I've forgotten this before." - Steven Wright
 
IP Logged
 
Chris Wright
WR Addict
*****
Offline


Woodturners: 21st century
Druids

Posts: 3,725

Los Angeles, CA, California, USA
Los Angeles, CA
California
USA

Gender: male
Re: Scraper Burnishing tool
Reply #3 - Sep 5th, 2005 at 7:41am
 
Hey Jim, just a user review, but the scraper burnisher is a nice idea, but to be perfectly honest, I can get a better burr on my scrapers (and one that lasts longer) on my grinder.
Back to top
  

Three Mutts Customs
Custom Leather, Wood & Metal gear
Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to Login or Register

"Striving for excellence motivates you; striving for perfection is demoralizing"
WWW  
IP Logged
 
Keith_Bundy
Senior Member
****
Offline


Ky. turner

Posts: 353

Gender: male
Re: Scraper Burnishing tool
Reply #4 - Sep 5th, 2005 at 10:03am
 
I have to agree with Chris on this, JIm.
Back to top
  
 
IP Logged
 
JimQuarles
WR Addict
WR Patron
*****
Offline


WR Rocks, BIG Time!

Posts: 13,194

Glendale, AZ, Arizona, USA
Glendale, AZ
Arizona
USA

Gender: male
Re: Scraper Burnishing tool
Reply #5 - Sep 5th, 2005 at 12:02pm
 
I must not be grinding it properly, because it just doesn't get much of  burr.  I have been just barely running it across the wheel at the same angle, and getting a little burr.  I used to get a better burr on my cabinet scrapers with a carbide rod than I am getting with the grinder.

JimQ
Back to top
  

Mentor Basics, Pens, small stuff, Acrylics, EasyRougher.
Just Turnin' Around! Glendale, AZ Cool Cool

"Right now I'm having amnesia and deja vu at the same time.
I think I've forgotten this before." - Steven Wright
 
IP Logged
 
Keith_Bundy
Senior Member
****
Offline


Ky. turner

Posts: 353

Gender: male
Re: Scraper Burnishing tool
Reply #6 - Sep 5th, 2005 at 7:11pm
 
Jim - What grit wheel are you using? I use an 80 and I get a nice burr. Try grinding with a little more pessure. You get a difference in the burr depending on how much pressure you apply and how many passes you make.
Back to top
  
 
IP Logged
 
JimQuarles
WR Addict
WR Patron
*****
Offline


WR Rocks, BIG Time!

Posts: 13,194

Glendale, AZ, Arizona, USA
Glendale, AZ
Arizona
USA

Gender: male
Re: Scraper Burnishing tool
Reply #7 - Sep 5th, 2005 at 7:56pm
 
I've got 60 & 100 grit wheels.  I have been using the 100 for general sharpening, and kept the 60 for when major reshaping would be needed.  It is a 3450 RPM grinder that came with 36 & 60 grit and I shelved the 36 after I sharpened the lawnmower blade.

I set the platform to match the angle on the scraper, and then just barely take anything off with the 100 grit.

JimQ
Back to top
  

Mentor Basics, Pens, small stuff, Acrylics, EasyRougher.
Just Turnin' Around! Glendale, AZ Cool Cool

"Right now I'm having amnesia and deja vu at the same time.
I think I've forgotten this before." - Steven Wright
 
IP Logged
 
DWFII
Junior Member
*
Offline



Posts: 25

Gender: male
Re: Scraper Burnishing tool
Reply #8 - Sep 6th, 2005 at 5:05am
 
For what it's worth I have the burnishing jig. I think I got it at Woodcraft. I use scrapers all the time...flat ones, curved ones, etc. ...on flat wood and on leather (I'm a full-time (30+ years), custom bootmaker).

In my work sharp knives are an absolute must. I'm not talking "somewhat, maybe-shave-your arm-hair" sharp, I'm talking "scary, cut-your-arm-off-if you-get-near-it" sharp. I understand about how to get that kind of edge and what the metal looks like and goes through getting there.

That  may, at first blush, seem beside the point, but really if you visualize what is going on when you sharpen any tool, you may think again about the jig. The grinder thins the metal out and it will, indeed, leave a thin burr or wire on the tool. But the problem is that it is just that-- "thin."

When you burnish the scraper...whether you use a jig or do it by hand (the jig isn't absolutely necessary) ...you roll metal into the base of that burr, for lack of a better way of describing it, and you strengthen and reinforce the burr.  It will last a lot longer and stay sharp longer than if you do not burnish the burr.

I like the jig in question. I use it religiously and I think it helps.  But that's just one man's opinion....for what it's worth.


DW
In the High Desert of Central Oregon
Back to top
« Last Edit: Sep 6th, 2005 at 5:07am by DWFII »  

DW--in the high desert of central Oregon
 
IP Logged
 
Boots
Full Member
**
Offline



Posts: 63

Gender: male
Re: Scraper Burnishing tool
Reply #9 - Sep 6th, 2005 at 1:38pm
 
Hi.
You have written "you roll metal into the base of the burr" can you explain as it means nothing to me. any chance of a picture,  Are you polishing the ground edge or the flat face, and in what dirrection? sorry to sound so stupid but if it helps I need to know how to do it.

Boots
Back to top
« Last Edit: Sep 6th, 2005 at 1:40pm by Boots »  
Boots Boots  
IP Logged
 
DWFII
Junior Member
*
Offline



Posts: 25

Gender: male
Re: Scraper Burnishing tool
Reply #10 - Sep 6th, 2005 at 2:15pm
 
Well, it's hard to describe but when you sharpen a scraper it creates a concave surface, sort of. Now it doesn't need that concave surface to create the burr but it helps if you visualize it that way. When you use the jig, you are pushing the leading edge of that concavity into the burnishing pin. The pressure you exert against the pin forces the concave edge upward, creating or reinforcing the burr.  Pushing/forcing/BURNISHING this concave edge will create a burr that is just as sharp but three or even four times as thick (and proportionately longer lasting) as the original burr.

Sharpening flat cabinet scrapers is similar...first you file/sharpen flat arcoss the edge of the scraper. (If you take the time to feel the flat surface of the scraper, you will feel a burr.) Then! Take the burnishing tool and, working across the flat surface (face) of the scraper push that burr back onto the edge. Burnishing the flat surface "spreads" metal (including the original burr) toward the edge. Now holding the burnisher at a slight angle run it across and along the edge....hard! This is usually done with the scraper clamped in a vise. Burnishing will roll the edge up into the face again, thus re-creating the burr except this time it will be (if you had a magnifying glass to examine it) maybe three times as thick at the base of the burr as it was originally.  I'm sorry if I'm confusing you but describing the cabinet scraper illustrates the point abut not needing a concave surface.

One other point that can be made that might help you understand the process is knowing that to create a really sharp edge on a knife, you must work up a burr  (sometimes called a "wire") on both sides of the knife--first on one side then the other. Fundamentally, these burrs are an indication that the metal has been thinned so much that it has bent over--creating the wire/burr. After working up a wire on both sides, stropping flexes that thin, weak metal until it breaks off. Well, the fact that it will break off, at all..and on leather,  speaks volumes about how long lasting a burr that is not burnished into the edge (of any tool--knife chisel, gouge, scraper) is going to be.

Well, again, I don't know how much help this has been...like a lot of things the knowledge is more in the hands than in the head. And others may have completely satisfactory results not burnishing at all....although I think the concepts are sound and consistant across disciplines. But if it helps, you're welcome to it.

PS, I don't think I have the skills (or the camera) to take a photo that close up to truly show what is going on. A flat cabinet scraper, for instance, is less than a mm wide and a knife edge disappears into infinity.  Try it both ways...or buy a burnishing tool for a cabinet scraper and read the instructions...once you get the hang of it though you'll be amazed at what a scraper can do or how sharp a knife can really be.
Back to top
« Last Edit: Sep 6th, 2005 at 2:30pm by DWFII »  

DW--in the high desert of central Oregon
 
IP Logged
 
Gil Jones
Ex Member


Re: Scraper Burnishing tool
Reply #11 - Sep 6th, 2005 at 8:08pm
 
Go to this web site and read all about it  (see pictures too).
Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to Login or Register
Back to top
  
 
IP Logged
 
DWFII
Junior Member
*
Offline



Posts: 25

Gender: male
Re: Scraper Burnishing tool
Reply #12 - Sep 7th, 2005 at 4:37am
 
Gil,

Yes. Thanks...that explains the concept much better than I could. 

I think the important point is that, theoretically at least, any burr created just by sharpening is really thin.  And really weak. Again, think of sharpening the knife. Gil's link states Quote:
"The final stage of scraper edge preparation is burnishing, where the tiny cutting hook is applied to the edge. This is the most critical part of the process, as even the sharpest scrapers will not work if they are not properly burnished."

My own experience, in wood and leather, with many different types of scrapers, bears that out.
Back to top
  

DW--in the high desert of central Oregon
 
IP Logged
 
Bob_Hadley
Full Member
**
Offline


I love YaBB 1G - SP1!

Posts: 77

Re: Scraper Burnishing tool
Reply #13 - Sep 12th, 2005 at 6:19am
 
There seems to be is a significant difference between the cutting actions of a burnished scraper and a ground-edge scraper.

Mainly I prefer the cutting action of the burr I get from my 80 grit grinder wheel for most applications. It is a more delicate burr and, in my opinion, allows a lighter, more controlled finish cut.

I find I can burnish an edge softer or harder to produce a relatively light or much more aggressive cut. But no matter how light I burnish, its still not quite as same as a light touch on the grinder for final-pass scraping. Not to mention the steps saved in getting back to the lathe (you must hone the grinder burr off the scraper prior to burnishing, lest your burr will end up with a jagged and brittle edge).

Incidentally, my grinder runs at 1725 rpm, which probably produces a slightly less aggressive burr than a 3450 rpm grinder.

BH
Back to top
  
 
IP Logged
 
Chris Wright
WR Addict
*****
Offline


Woodturners: 21st century
Druids

Posts: 3,725

Los Angeles, CA, California, USA
Los Angeles, CA
California
USA

Gender: male
Re: Scraper Burnishing tool
Reply #14 - Sep 12th, 2005 at 7:52am
 
I think Bob hit the nail on the head.  A grinder burr (which by the way I do like Keith, add pressure - I have a 100 grit white wheel on a 3450 grinder) doesn't last as long, but for true scraping, which should be a clean up tool, not a roughing or shaping tool I like the burr thinner and weaker as it will pull finer cuts that when I burnish and it is faster and easier to replace.  My grinder is two steps from the lathe and I free hand my scraper grinder, so it takes about 8 seconds total to get a new burr, if I had to burnish too, that would add a walk across the shop and another 10-15 seconds to the time, over the course of an 8 hour turning day, I might lose up to 15-20 minutes by burnishing and that equals 1-2 small projects or in other words $$. 

Granted, if this is completely a hobby and time/speed doesn't matter, then it's no big deal.
Back to top
  

Three Mutts Customs
Custom Leather, Wood & Metal gear
Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to Login or Register

"Striving for excellence motivates you; striving for perfection is demoralizing"
WWW  
IP Logged
 
Page Index Toggle Pages: 1
Send Topic Print